IIT 4-Way Flat Tester with LED

Name: IIT 4-Way Flat Tester with LED
SKU: 152641
Availability: InStock

$3.86

SKU: 152641 Categories: Automotive, Battery Accessories

In stock

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The IIT 4-Way Flat Tester with LED is an essential diagnostic tool for anyone who regularly hauls trailers, boats, or utility carts through the unpredictable Missouri weather. When your trailer lights fail to illuminate, this compact device takes the guesswork out of the repair by immediately identifying whether the problem lies in your vehicle’s wiring or the trailer itself. By simply plugging the tester into the 4-way flat connector on your truck or SUV, you can visually confirm that power is reaching the socket for every major lighting function. This prevents you from wasting time stripping wires on a trailer when the actual culprit is a blown fuse or a faulty relay in your tow vehicle.

Key Features of IIT 4-Way Flat Tester with LED

Bright LED indicators provide instant visual confirmation for each electrical circuit

Tests essential towing functions including tail lights, brake lights, and both turn signals

Compact, plug-and-play design fits directly into any standard 4-way flat vehicle socket

Durable weather-resistant housing protects the internal circuitry from impact and moisture

Eliminates the need for a second person to stand behind the vehicle during light checks

Small enough to be stored permanently in a glove box, center console, or door pocket

Helps pinpoint ground wire issues which are a common cause of trailer lighting failure

Heavy-duty construction ensures reliable performance for professional or DIY use

Additional Information

Brand: IIT

Product Type: Trailer Wiring Tester

Model:

Product Use: Diagnosing vehicle-side trailer lighting and electrical circuits

Size: 4-way flat standard

Material: Impact-resistant PVC with brass terminals

Height: 1/2 inch

Length: 3 inch

Width: 2 inch

To perform a complete test, plug the device into your vehicle and cycle through your lights one by one: turn on the headlights to check the “Tail” circuit, then have a partner tap the brakes and engage each turn signal. If the LEDs on the tester light up but your trailer lights still do not work when connected, you know the issue is definitely on the trailer side, likely a burnt bulb or a broken wire. It is a good habit to plug this tester in before every long trip; a ten-second check can save you from a costly fix or a safety citation on the road.